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1.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595132

RESUMO

Horizontal gene transfer (HGT) is a means of exchanging genetic material asexually. The process by which horizontally transferred genes are domesticated by the host genome is of great interest but is not well understood. In this study, we determined the telomere-to-telomere genome sequence of the wheat-infecting Pyricularia oryzae strain Br48. SNP analysis indicated that the Br48 strain is a hybrid of wheat- and Brachiaria-infecting strains by a sexual or parasexual cross. Comparative genomic analysis identified several megabase-scale "insertions" in the Br48 genome, some of which were possibly gained by HGT-related events from related species, such as P. pennisetigena or P. grisea. Notably, the mega-insertions often contained genes whose phylogeny is not congruent with the species phylogeny. Moreover, some of the genes have a close homolog even in distantly related organisms, such as basidiomycetes or prokaryotes, implying the involvement of multiple HGT events. Interestingly, the levels of the silent epigenetic marks H3K9me3 and H3K27me3 in a genomic region tended to be negatively correlated with the phylogenetic concordance of genes in the same region, suggesting that horizontally transferred DNA is preferentially targeted for epigenetic silencing. Indeed, the putative HGT-derived genes were activated when MoKmt6, the gene responsible for H3K27me3 modification, was deleted. Notably, these genes also tended to be up-regulated during infection, suggesting that they are now under host control and have contributed to establishing a fungal niche. In conclusion, this study suggests that epigenetic modifications have played an important role in the domestication of HGT-derived genes in the P. oryzae genome.


Assuntos
Ascomicetos , Código das Histonas , Histonas/genética , Filogenia , DNA , Ascomicetos/genética , Triticum
2.
Plant Cell Physiol ; 64(1): 94-106, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36222360

RESUMO

Rice is the model C3 crop for investigating the starch biosynthesis mechanism in endosperm because of its importance in grain production. However, little is known about starch biosynthesis in the vegetative organs of rice. In this study, we used novel rice mutants by inserting Tos17 into the starch synthase (SS) IIIb gene, which is mainly expressed in the leaf sheath (LS) and leaf blade (LB), and an ss1 mutant to clarify the differences in roles among SS isozymes during starch biosynthesis. Native polyacrylamide gel electrophoresis (PAGE)/activity staining for SS, using LS and LB of ss mutants, revealed that the lowest migrating SS activity bands on the gel were derived from SSIIIb activity and those of two ss3b mutants were not detected. The apparent amylose content of LS starch of ss3b mutants increased. Moreover, the chain-length distribution and size-exclusion chromatography analysis using ss mutants showed that SSIIIb and SSI synthesize the B2-B3 chain and A-B1 chain of amylopectin in the LS and LB respectively. Interestingly, we also found that starch contents were decreased in the LS and LB of ss3b mutants, although SSI deficiency did not affect the starch levels. All these results indicated that SSIIIb synthesizes the long chain of amylopectin in the LS and LB similar to SSIIIa in the endosperm, while SSI synthesizes the short chain in the vegetative organ as the same in the endosperm.


Assuntos
Oryza , Sintase do Amido , Amilopectina , Oryza/genética , Sintase do Amido/genética , Sementes/genética , Amido , Amilose
3.
Blood ; 137(7): 908-922, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33174606

RESUMO

Epigenetic regulation is essential for the maintenance of the hematopoietic system, and its deregulation is implicated in hematopoietic disorders. In this study, UTX, a demethylase for lysine 27 on histone H3 (H3K27) and a component of COMPASS-like and SWI/SNF complexes, played an essential role in the hematopoietic system by globally regulating aging-associated genes. Utx-deficient (UtxΔ/Δ) mice exhibited myeloid skewing with dysplasia, extramedullary hematopoiesis, impaired hematopoietic reconstituting ability, and increased susceptibility to leukemia, which are the hallmarks of hematopoietic aging. RNA-sequencing (RNA-seq) analysis revealed that Utx deficiency converted the gene expression profiles of young hematopoietic stem-progenitor cells (HSPCs) to those of aged HSPCs. Utx expression in hematopoietic stem cells declined with age, and UtxΔ/Δ HSPCs exhibited increased expression of an aging-associated marker, accumulation of reactive oxygen species, and impaired repair of DNA double-strand breaks. Pathway and chromatin immunoprecipitation analyses coupled with RNA-seq data indicated that UTX contributed to hematopoietic homeostasis mainly by maintaining the expression of genes downregulated with aging via demethylase-dependent and -independent epigenetic programming. Of note, comparison of pathway changes in UtxΔ/Δ HSPCs, aged muscle stem cells, aged fibroblasts, and aged induced neurons showed substantial overlap, strongly suggesting common aging mechanisms among different tissue stem cells.


Assuntos
Envelhecimento/genética , Regulação da Expressão Gênica/genética , Hematopoese/genética , Sistema Hematopoético/fisiologia , Código das Histonas/genética , Histona Desmetilases/fisiologia , Animais , Senescência Celular/genética , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Feminino , Predisposição Genética para Doença , Hematopoese Extramedular , Histona Desmetilases/deficiência , Histona Desmetilases/genética , Reconstituição Imune , Histona Desmetilases com o Domínio Jumonji/metabolismo , Leucemia Experimental/genética , Leucemia Experimental/virologia , Masculino , Camundongos , Camundongos Knockout , Vírus da Leucemia Murina de Moloney/fisiologia , Células Mieloides/patologia , Quimera por Radiação , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/metabolismo , Fatores de Transcrição/metabolismo , Integração Viral
4.
BMC Cancer ; 20(1): 688, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703191

RESUMO

BACKGROUND: Although surgery is the definitive curative treatment for biliary tract cancer (BTC), outcomes after surgery alone have not been satisfactory. Adjuvant therapy with S-1 may improve survival in patients with BTC. This study examined the safety and efficacy of 1 year adjuvant S-1 therapy for BTC in a multi-institutional trial. METHODS: The inclusion criteria were as follows: histologically proven BTC, Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, R0 or R1 surgery performed, cancer classified as Stage IB to III. Within 10 weeks post-surgery, a 42-day cycle of treatment with S-1 (80 mg/m2/day orally twice daily on days 1-28 of each cycle) was initiated and continued up to 1 year post surgery. The primary endpoint was adjuvant therapy completion rate. The secondary endpoints were toxicities, disease-free survival (DFS), and overall survival (OS). RESULTS: Forty-six patients met the inclusion criteria of whom 19 had extrahepatic cholangiocarcinoma, 10 had gallbladder carcinoma, 9 had ampullary carcinoma, and 8 had intrahepatic cholangiocarcinoma. Overall, 25 patients completed adjuvant chemotherapy, with a 54.3% completion rate while the completion rate without recurrence during the 1 year administration was 62.5%. Seven patients (15%) experienced adverse events (grade 3/4). The median number of courses administered was 7.5. Thirteen patients needed dose reduction or temporary therapy withdrawal. OS and DFS rates at 1/2 years were 91.2/80.0% and 84.3/77.2%, respectively. Among patients who were administered more than 3 courses of S-1, only one patient discontinued because of adverse events. CONCLUSIONS: One-year administration of adjuvant S-1 therapy for resected BTC was feasible and may be a promising treatment for those with resected BTC. Now, a randomized trial to determine the optimal duration of S-1 is ongoing. TRIAL REGISTRATION: UMIN-CTR, UMIN000009029. Registered 5 October 2012-Retrospectively registered, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000009347.


Assuntos
Neoplasias dos Ductos Biliares/tratamento farmacológico , Ácido Oxônico/administração & dosagem , Tegafur/administração & dosagem , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampola Hepatopancreática , Neoplasias dos Ductos Biliares/cirurgia , Carcinoma/tratamento farmacológico , Carcinoma/cirurgia , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/cirurgia , Intervalo Livre de Doença , Esquema de Medicação , Combinação de Medicamentos , Estudos de Viabilidade , Feminino , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Oxônico/efeitos adversos , Estudos Prospectivos , Tegafur/efeitos adversos , Resultado do Tratamento
5.
Nucleic Acids Res ; 46(5): 2495-2508, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29309640

RESUMO

Small RNA (sRNA)-mediated gene silencing phenomena, exemplified by RNA interference (RNAi), require a unique class of proteins called Argonautes (AGOs). An AGO protein typically forms a protein-sRNA complex that contributes to gene silencing using the loaded sRNA as a specificity determinant. Here, we show that MoAGO2, one of the three AGO genes in the fungus Pyricularia oryzae (Magnaporthe oryzae) interferes with RNAi. Gene knockout (KO) studies revealed that MoAGO1 and MoAGO3 additively or redundantly played roles in hairpin RNA- and retrotransposon (MAGGY)-triggered RNAi while, surprisingly, the KO mutants of MoAGO2 (Δmoago2) showed elevated levels of gene silencing. Consistently, transcript levels of MAGGY and mycoviruses were drastically reduced in Δmoago2, supporting the idea that MoAGO2 impeded RNAi against the parasitic elements. Deep sequencing analysis revealed that repeat- and mycovirus-derived small interfering RNAs were mainly associated with MoAGO2 and MoAGO3, and their populations were very similar based on their size distribution patterns and positional base preference. Site-directed mutagenesis studies indicated that sRNA binding but not slicer activity of MoAGO2 was essential for the ability to diminish the efficacy of RNAi. Overall, these results suggest a possible interplay between distinct sRNA-mediated gene regulation pathways through a competition for sRNA.


Assuntos
Proteínas Argonautas/metabolismo , Proteínas Fúngicas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Argonautas/biossíntese , Proteínas Argonautas/genética , Proteínas Argonautas/fisiologia , Ascomicetos/genética , Ascomicetos/virologia , Grânulos Citoplasmáticos/metabolismo , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Micovírus/genética , Deleção de Genes , Genoma Fúngico , Retroelementos
6.
Plant Cell Physiol ; 60(5): 961-972, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690625

RESUMO

CO2-responsive CCT protein (CRCT) is suggested to be a positive regulator of starch biosynthesis in the leaf sheaths of rice, regulating the expression levels of starch biosynthesis-related genes. In this study, the effects of CRCT expression levels on the expression of starch biosynthesis-related enzymes and the quality of starch were studied. Using native-PAGE/activity staining and immunoblotting, we found that the protein levels of starch synthase I, branching enzyme I, branching enzyme IIa, isoamylase 1 and phosphorylase 1 were largely correlated with the CRCT expression levels in the leaf sheaths of CRCT transgenic lines. In contrast, the CRCT expression levels largely did not affect the expression levels and/or activities of starch biosynthesis-related enzymes in the leaf blades and endosperm tissues. The analysis of the chain-length distribution of starch in the leaf sheaths showed that short chains with a degree of polymerization from 5 to 14 were increased in the overexpression lines but decreased in the knockdown lines. The amylose content of starch in the leaf sheath was greatly increased in the overexpression lines. In contrast, the molecular weight of the amylopectin of starch in the leaf sheath of overexpression lines did not change compared with those of the non-transgenic rice. These results suggest that CRCT can control the quality and the quantity of starch in the leaf sheath by regulating the expression of particular starch biosynthesis-related enzymes.


Assuntos
Dióxido de Carbono/metabolismo , Oryza/metabolismo , Folhas de Planta/metabolismo , Amido/metabolismo , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilose/metabolismo , Isoamilase/metabolismo , Sintase do Amido/metabolismo
7.
Blood ; 129(15): 2148-2160, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28209720

RESUMO

Chronic myelomonocytic leukemia (CMML) is a hematological malignancy characterized by uncontrolled proliferation of dysplastic myelomonocytes and frequent progression to acute myeloid leukemia (AML). We identified mutations in the Cbl gene, which encodes a negative regulator of cytokine signaling, in a subset of CMML patients. To investigate the contribution of mutant Cbl in CMML pathogenesis, we generated conditional knockin mice for Cbl that express wild-type Cbl in a steady state and inducibly express CblQ367P , a CMML-associated Cbl mutant. CblQ367P mice exhibited sustained proliferation of myelomonocytes, multilineage dysplasia, and splenomegaly, which are the hallmarks of CMML. The phosphatidylinositol 3-kinase (PI3K)-AKT and JAK-STAT pathways were constitutively activated in CblQ367P hematopoietic stem cells, which promoted cell cycle progression and enhanced chemokine-chemokine receptor activity. Gem, a gene encoding a GTPase that is upregulated by CblQ367P , enhanced hematopoietic stem cell activity and induced myeloid cell proliferation. In addition, Evi1, a gene encoding a transcription factor, was found to cooperate with CblQ367P and progress CMML to AML. Furthermore, targeted inhibition for the PI3K-AKT and JAK-STAT pathways efficiently suppressed the proliferative activity of CblQ367P -bearing CMML cells. Our findings provide insights into the molecular mechanisms underlying mutant Cbl-induced CMML and propose a possible molecular targeting therapy for mutant Cbl-carrying CMML patients.


Assuntos
Ciclo Celular , Células-Tronco Hematopoéticas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Mutação de Sentido Incorreto , Mielopoese , Proteínas Proto-Oncogênicas c-cbl , Regulação para Cima , Substituição de Aminoácidos , Animais , Regulação Enzimológica da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Transgênicos , Monócitos/metabolismo , Monócitos/patologia , Proteínas Monoméricas de Ligação ao GTP/biossíntese , Proteínas Monoméricas de Ligação ao GTP/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-cbl/biossíntese , Proteínas Proto-Oncogênicas c-cbl/genética , Transdução de Sinais
8.
PLoS Genet ; 11(7): e1005385, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26230995

RESUMO

Here we report the genetic analyses of histone lysine methyltransferase (KMT) genes in the phytopathogenic fungus Magnaporthe oryzae. Eight putative M. oryzae KMT genes were targeted for gene disruption by homologous recombination. Phenotypic assays revealed that the eight KMTs were involved in various infection processes at varying degrees. Moset1 disruptants (Δmoset1) impaired in histone H3 lysine 4 methylation (H3K4me) showed the most severe defects in infection-related morphogenesis, including conidiation and appressorium formation. Consequently, Δmoset1 lost pathogenicity on wheat host plants, thus indicating that H3K4me is an important epigenetic mark for infection-related gene expression in M. oryzae. Interestingly, appressorium formation was greatly restored in the Δmoset1 mutants by exogenous addition of cAMP or of the cutin monomer, 16-hydroxypalmitic acid. The Δmoset1 mutants were still infectious on the super-susceptible barley cultivar Nigrate. These results suggested that MoSET1 plays roles in various aspects of infection, including signal perception and overcoming host-specific resistance. However, since Δmoset1 was also impaired in vegetative growth, the impact of MoSET1 on gene regulation was not infection specific. ChIP-seq analysis of H3K4 di- and tri-methylation (H3K4me2/me3) and MoSET1 protein during infection-related morphogenesis, together with RNA-seq analysis of the Δmoset1 mutant, led to the following conclusions: 1) Approximately 5% of M. oryzae genes showed significant changes in H3K4-me2 or -me3 abundance during infection-related morphogenesis. 2) In general, H3K4-me2 and -me3 abundance was positively associated with active transcription. 3) Lack of MoSET1 methyltransferase, however, resulted in up-regulation of a significant portion of the M. oryzae genes in the vegetative mycelia (1,491 genes), and during infection-related morphogenesis (1,385 genes), indicating that MoSET1 has a role in gene repression either directly or more likely indirectly. 4) Among the 4,077 differentially expressed genes (DEGs) between mycelia and germination tubes, 1,201 and 882 genes were up- and down-regulated, respectively, in a Moset1-dependent manner. 5) The Moset1-dependent DEGs were enriched in several gene categories such as signal transduction, transport, RNA processing, and translation.


Assuntos
Metilação de DNA/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Magnaporthe/patogenicidade , Morfogênese/genética , AMP Cíclico/metabolismo , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Técnicas de Inativação de Genes , Genes Fúngicos/genética , Hordeum/microbiologia , Magnaporthe/enzimologia , Magnaporthe/genética , Micélio/genética , Ácidos Palmíticos/metabolismo , Doenças das Plantas/microbiologia , Esporos Fúngicos/crescimento & desenvolvimento , Transcrição Gênica/genética , Triticum/microbiologia
9.
J Stroke Cerebrovasc Dis ; 27(4): 998-1002, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29221971

RESUMO

BACKGROUND: Changes in regional cerebral blood flow (rCBF) were reported in migraineurs. However, little is known how preventive medications of migraine can influence rCBF. Lomerizine, a calcium channel blocker, has been used for migraine prophylaxis in Japan. We examined rCBF after lomerizine treatment. SUBJECTS AND METHODS: Migraine was diagnosed according to the criteria of the International Classification of Headache Disorders, Third Edition beta. Migraine subtype was classified into migraine with aura (MA) and migraine without aura (MO). Lomerizine (10 mg/day, per oral) was administered for 3 months. Headache Impact Test-6 (HIT-6) and blood pressure (BP) were compared at baseline and end point. Brain single photon emission computed tomography using 99mTc-ethyl cysteinate dimer was performed at the interictal period. Brain SPECT data were analyzed according to revised version of 3-dimensional stereotaxic region of interest template. Clinic-radiological variables were analyzed by paired Student's t test. RESULTS: Ten migraineurs (4 men and 6 women) participated in the present study. Mean age was 54.1 (standard deviation [SD] 10.1) years. Mean duration of migraine was 25.3 (SD 9.8) years. Migraine subtype showed 4 MA and 6 MO patients. Mean score of HIT-6 was 66.3 (SD 11.7). Lomerizine treatment decreased HIT-6 scores significantly (P < .01). BP did not differ significantly after lomerizine treatment. Lomerizine treatment increased rCBF 20% approximately in the frontal, the parietal, the temporal, and the occipital region. CONCLUSIONS: The present study indicated a significant increase in interictal rCBF after lomerizine treatment in migraineurs. The upregulation of rCBF could contribute to the antimigraine mechanism of lomerizine.


Assuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Circulação Cerebrovascular/efeitos dos fármacos , Enxaqueca com Aura/prevenção & controle , Enxaqueca sem Aura/prevenção & controle , Piperazinas/uso terapêutico , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Bloqueadores dos Canais de Cálcio/efeitos adversos , Cisteína/administração & dosagem , Cisteína/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enxaqueca com Aura/diagnóstico por imagem , Enxaqueca com Aura/fisiopatologia , Enxaqueca sem Aura/diagnóstico por imagem , Enxaqueca sem Aura/fisiopatologia , Compostos de Organotecnécio/administração & dosagem , Imagem de Perfusão/métodos , Piperazinas/efeitos adversos , Compostos Radiofarmacêuticos/administração & dosagem , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
10.
Plant Physiol ; 170(4): 2024-39, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26884484

RESUMO

Lipid-derived reactive carbonyl species (RCS) possess electrophilic moieties and cause oxidative stress by reacting with cellular components. Arabidopsis (Arabidopsis thaliana) has a chloroplast-localized alkenal/one oxidoreductase (AtAOR) for the detoxification of lipid-derived RCS, especially α,ß-unsaturated carbonyls. In this study, we aimed to evaluate the physiological importance of AtAOR and analyzed AtAOR (aor) mutants, including a transfer DNA knockout, aor (T-DNA), and RNA interference knockdown, aor (RNAi), lines. We found that both aor mutants showed smaller plant sizes than wild-type plants when they were grown under day/night cycle conditions. To elucidate the cause of the aor mutant phenotype, we analyzed the photosynthetic rate and the respiration rate by gas-exchange analysis. Subsequently, we found that both wild-type and aor (RNAi) plants showed similar CO2 assimilation rates; however, the respiration rate was lower in aor (RNAi) than in wild-type plants. Furthermore, we revealed that phosphoenolpyruvate carboxylase activity decreased and starch degradation during the night was suppressed in aor (RNAi). In contrast, the phenotype of aor (RNAi) was rescued when aor (RNAi) plants were grown under constant light conditions. These results indicate that the smaller plant sizes observed in aor mutants grown under day/night cycle conditions were attributable to the decrease in carbon utilization during the night. Here, we propose that the detoxification of lipid-derived RCS by AtAOR in chloroplasts contributes to the protection of dark respiration and supports plant growth during the night.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Carbono/metabolismo , Cloroplastos/enzimologia , Escuridão , Oxirredutases Atuantes sobre Doadores de Grupos Aldeído ou Oxo/metabolismo , Oxirredutases/metabolismo , Folhas de Planta/enzimologia , Supressão Genética , Acroleína/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , Respiração Celular/efeitos da radiação , Clorofila/metabolismo , Cloroplastos/efeitos da radiação , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Mutação/genética , Nitrogênio/metabolismo , Oxirredutases Atuantes sobre Doadores de Grupos Aldeído ou Oxo/genética , Fenótipo , Fotossíntese , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Amido/metabolismo
11.
Photosynth Res ; 131(1): 41-50, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27432175

RESUMO

Light and temperature affect state transitions through changes in the plastoquinone (PQ) redox state in photosynthetic organisms. We demonstrated that light and/or heat treatment induced preferential photosystem (PS) I excitation by binding light-harvesting complex II (LHCII) proteins. The photosystem of wheat was in state 1 after dark overnight treatment, wherein PQ was oxidized and most of LHCII was not bound to PSI. At the onset of the light treatment [25 °C in the light (100 µmol photons m-2 s-1)], two major LHCIIs, Lhcb1 and Lhcb2 were phosphorylated, and the PSI-LHCII supercomplex formed within 5 min, which coincided with an increase in the PQ oxidation rate. Heat treatment at 40 °C of light-adapted wheat led to further LHCII protein phosphorylation of, resultant cyclic electron flow promotion, which was accompanied by ultrafast excitation of PSI and structural changes of thylakoid membranes, thereby protecting PSII from heat damage. These results suggest that LHCIIs are required for the functionality of wheat plant PSI, as it keeps PQ oxidized by regulating photochemical electron flow, thereby helping acclimation to environmental changes.


Assuntos
Adaptação Fisiológica , Temperatura Alta , Complexos de Proteínas Captadores de Luz/química , Luz , Complexo de Proteína do Fotossistema I/química , Fosforilação , Espectrometria de Fluorescência , Tilacoides/metabolismo
12.
Neurol Sci ; 38(5): 827-831, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28224326

RESUMO

Lomerizine, calcium channel blocker, is the most used medication for migraine prophylaxis in Japan. The effectiveness of this drug is reported as 50-75%. Telmisartan is angiotensin II receptor blockers which plasma half-life is 24 h. We examined whether telmisartan has preventative benefits in lomerizine non-responsive migraineurs. Lomerizine non-responders received telmisartan (20 mg/day) for 3 months after the investigation period of 3 months. Blood pressure, frequency of headache days/month, headache severity, and doses of triptans and analgesics were analyzed by Wilcoxon signed rank test. Thirty-three migraineurs (25 women and 8 men) participated in this study. Seven patients had migraine with aura and 26 patients had migraine without aura. Mean age (SD) was 46.6 (10.3) years. Mean duration (SD) of migraine was 20.4 (12.5) years. Headache severity exhibited mild degree in 5 patients, moderate degree in 9 patients and severe degree in 19 patients. Mean frequency (SD) of headache days was 10.9 (8.5) days/month. Mean usage (SD) of triptans was 4.8 (5.1) tablets/month and that of analgesics was 15.2 (22.2) tablets/month. Five patients (15%) had hypertension. Telmisartan administration had benefits in 30 patients (90%). This medication significantly decreased frequency of headache days (P < 0.01) and headache severity (P < 0.01). Doses of triptans were reduced at one-third (P < 0.05) and those of analgesia at one-fifth after telmisartan treatment (P < 0.01). After telmisartan, mean (SD) of systolic blood pressure was significantly decreased (P < 0.05). The present study supported that telmisartan treatment had preventive effects in 90% of lomerizine non-responders. Telmisartan non-responders (10%) exhibited chronic migraine and long migraine duration.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Transtornos de Enxaqueca/prevenção & controle , Adulto , Bloqueadores dos Canais de Cálcio/efeitos adversos , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Piperazinas/efeitos adversos , Índice de Gravidade de Doença , Telmisartan
13.
J Stroke Cerebrovasc Dis ; 26(3): 644-649, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27939141

RESUMO

BACKGROUND: Antiepileptic drugs (AEDs) may increase development of dyslipidemia and cerebrovascular disease (CVD). We examined the clinical profile and changes of serum lipid levels after AED monotherapy in patients with poststroke epilepsy (PSE) after cerebral infarction (CI). SUBJECTS AND METHODS: Medical records were reviewed in consecutive 2144 CI patients. Monotherapy of valproate, carbamazepine (CBZ), phenytoin (PHT), zonisamide, levetiracetam, or lamotrigine was performed in PSE patients. Serum lipid levels were measured before and at 3 months after AED treatment. RESULTS: The prevalence of PSE was 7.0% in CI patients. The TOAST etiology disclosed large-artery atherosclerosis in 68 patients (45%), cardioembolism in 63 patients (42%), and undetermined cause in 19 patients (13%). CVD risk profile showed obesity of 18 patients (12%), current smoker of 30 patients (20%), hypertension of 75 patients (50%), diabetes mellitus of 32 patients (21%), dyslipidemia of 15 patients (10%), and atrial fibrillation of 63 patients (42%). CBZ or PHT administration increased serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) levels significantly compared to baseline and AED-untreated controls. Those levels were not increased significantly in other AED and control groups. Serum high-density lipoprotein-cholesterol and triglyceride levels did not differ statistically in all groups. CONCLUSIONS: The prevalence of post-CI epilepsy was 7.0%. The pathogenesis contributed to atherothrombosis and cardioembolism. CBZ or PHT administration increased serum TC and LDL-C significantly. Thus, we should pay more attention to serum lipid levels in patients receiving cytochrome P450 (CYP)-induced AEDs, and might considerer switching to non-CYP-induced AEDs in patients with unfavorable serum lipid changes.


Assuntos
Infarto Cerebral/complicações , Epilepsia/sangue , Epilepsia/etiologia , Lipídeos/sangue , Idoso , Idoso de 80 Anos ou mais , Anticonvulsivantes/efeitos adversos , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
14.
Plant Cell Physiol ; 57(11): 2334-2341, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27519315

RESUMO

CO2-responsive CCT protein (CRCT) is the suggested positive regulator of starch synthesis in vegetative organs, particularly the leaf sheath of rice. In this study, we analyzed the effects of the starch level in the leaf sheath on the photosynthetic rate in the leaf blade using CRCT overexpression and RNA interference (RNAi) knockdown transgenic rice grown under ambient (38 Pa) or elevated (100 Pa) CO2 conditions. In leaf sheath, the starch content was markedly changed in relation to CRCT expression levels under both CO2 conditions. In contrast, the soluble sugar and starch contents of the leaf blade were markedly increased in the knockdown line grown under elevated CO2 conditions. The overexpression or RNAi knockdown of CRCT did not cause large effects on the photosynthetic rate of the transgenic lines grown under ambient CO2 condition. However, the photosynthetic rate of the overexpression line was enhanced, while that of the knockdown line was substantially decreased under elevated CO2 conditions. These photosynthetic rates were weakly correlated with the nitrogen contents and negatively correlated with the total non-structural carbohydrate contents. Thus, the capacity for starch synthesis in leaf sheath, which is controlled by CRCT, can indirectly affect the carbohydrate content, and then the photosynthetic rate in the leaf blade of rice grown under elevated CO2 conditions.


Assuntos
Dióxido de Carbono/farmacologia , Oryza/fisiologia , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Amido/metabolismo , Biomassa , Metabolismo dos Carboidratos/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Células do Mesofilo/efeitos dos fármacos , Células do Mesofilo/metabolismo , Células do Mesofilo/ultraestrutura , Nitrogênio/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Solubilidade
15.
BMC Neurol ; 16: 21, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26861945

RESUMO

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive sterol storage disease caused by a mutated sterol 27-hydroxylase (CYP27A1) gene. Patients with typical CTX show neurological dysfunction including bilateral cataracts, paresis, cerebral ataxia, dementia, and psychiatric disorders, and magnetic resonance imaging (MRI) has revealed symmetrical lesions in the cerebellar white matter. CASE PRESENTATION: We report the case of a patient with late-onset spinal form CTX without brain lesion. He showed pyramidal tract signs, and impaired joint position and vibration sensation in the lower limbs. Cervical sagittal MRI demonstrated a longitudinally extensive white matter abnormality in the dorsal column of the C2-C7 spinal cord; however, a brain MRI revealed an absence of lesions, including in the cerebellar white matter. Genetic analysis of CYP27A1 revealed that the patient was compound heterozygous for p.Gln85Arg in exon 1, a novel mutation, and p.Arg405Gln in exon 7, a previously reported mutation. CONCLUSION: This is the first report of late-onset spinal form CTX without typical neurological symptoms, and the first report of p.Gln85Arg in CYP27A1. We speculate that spinal form CTX without brain lesion is a clinically and radiologically rare variation of CTX. Therefore, spinal xanthomatosis should be included in the differential diagnosis of chronic myelopathy even with late-onset and/or no other typical neurological findings.


Assuntos
Colestanotriol 26-Mono-Oxigenase/genética , Imageamento por Ressonância Magnética/métodos , Xantomatose Cerebrotendinosa/fisiopatologia , Idoso , Encéfalo/patologia , Demência/etiologia , Éxons , Humanos , Masculino , Mutação , Medula Espinal/patologia , Xantomatose Cerebrotendinosa/genética
17.
J Stroke Cerebrovasc Dis ; 23(9): 2444-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25174565

RESUMO

BACKGROUND: Pathologic findings of cerebral amyloid angiopathy (CAA) and Alzheimer disease (AD) coexist frequently. Both diseases are associated with ß-amyloid deposition and dementia. We aimed to evaluate frequency and clinicoradiological profile of AD patients with multiple microbleeds (MBs). METHODS: We reviewed clinical records and magnetic resonance imaging (MRI) findings in patients with probable AD diagnosed by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), and National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria from 2009 to 2012. Brain MRI was performed at 1.5-T superconducting system, including T2*-weighted gradient-echo imaging. MBs were defined as rounded, hypointense foci less than or equal to 10 mm in size in the brain parenchyma. MBs topography was divided into the lobar (L) and the deep/infratentorial (D/I) region. Multiple MBs were defined as the number greater than or equal to 8 in the L and the D/I territory, respectively. White matter hyperintensities (WMHs) were assessed using the age-related white matter changes scale. Clinicoradiological findings were examined for 1 year. Prevalence and clinicoradiological profiles were studied in patients with multiple L or D/I MBs. RESULTS: Five hundred fifty patients (238 men and 312 women) participated in the present study. Mean age (standard deviation) was 78.4 (7.7) years, 78.3 (8.1) years in men and 78.6 (7.5) years in women. A total of 132 patients (55 men and 78 women) had at least 1 MB. Prevalence of MB ≥ 1 was 24%, 23 in men and 25 in women. The ratio of L and D/I MBs were 1.1, .6 in men and 1.8 in women. Multiple MBs were detected in 93 patients (17%), 38 (16%) men and 55 (17%) in women. L distribution was found in 49 patients (9%), 15 men (6%) and 34 women (11%), and D/I distribution in 44 patients (8%), 23 men (10%) and 21 women (7%). Multiple L MBs was associated with faster progression of dementia, cerebral hemorrhage, and increased number of MBs. Multiple D/I MBs were linked to hypertension and WMH scores. CONCLUSIONS: The present study indicated that the prevalence of multiple MBs was 17% in Japanese AD patients. The clinicoradiological profile suggested severe degree of CAA in patients with multiple L MBs (9%) and hypertension and aged changes in patients with multiple D/I MBs (8%). T2*-weighted imaging is a useful tool for evaluating degree of CAA and hypertensive vascular changes. We should pay more attention to management and care in AD patients with multiple MBs.


Assuntos
Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Povo Asiático/estatística & dados numéricos , Angiografia Cerebral , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico por imagem , Feminino , Humanos , Hemorragias Intracranianas/complicações , Hemorragias Intracranianas/diagnóstico por imagem , Japão/epidemiologia , Imageamento por Ressonância Magnética , Masculino , Microcirculação , Testes Neuropsicológicos , Prevalência , Fatores de Risco
18.
J Stroke Cerebrovasc Dis ; 23(3): 592-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23791468

RESUMO

A 49-year-old healthy man developed sudden unconsciousness under inadequate ventilation. Blood gas analysis showed carboxyhemoglobin of 7.3%. After normobaric oxygen therapy, he recovered completely 7 days later. At 3 weeks after carbon monoxide (CO) exposures, memory and gait disturbances appeared. Neurological examination revealed Mini-Mental State Examination (MMSE) score of 5 of 30 points, leg hyper-reflexia with Babinski signs, and Parkinsonism. Brain fluid-attenuated inversion recovery imaging disclosed symmetric hypointense lesions in the thalamus and the globus pallidus, and hyperintense lesions in the cerebral white matter. Brain single-photon emission tomography (SPECT) scanning with (99m)Technesium-ethyl cysteinate dimer displayed marked hypoperfusion in the cerebellum, the thalamus, the basal ganglia, and the entire cerebral cortex. He was diagnosed as CO poisoning and treated with hyperbaric oxygen therapy. The neurological deficits were not ameliorated. At 9 weeks after neurological onset, methylprednisolone (1000 mg/day, intravenous, 3 days) and memantine hydrochloride (20 mg/day, per os) were administered. Three days later, MMSE score was increased from 3 to 20 points. Neurological examination was normal 3 weeks later. Brain SPECT exhibited 20% increase of regional cerebral blood flows in the cerebellum, the thalamus, the basal ganglia, and the entire cerebral cortex. These clinicoradiological changes supported that the treatment with steroid pulse and memantine hydrochloride could prompt recovery from neurological dysfunction and cerebral hypoperfusion. Further clinical trials are warranted whether such combined therapy can attenuate neurological deficits and cerebral hypoperfusion in patients with CO poisoning.


Assuntos
Antiparkinsonianos/uso terapêutico , Intoxicação por Monóxido de Carbono/tratamento farmacológico , Circulação Cerebrovascular/efeitos dos fármacos , Transtornos Cerebrovasculares/tratamento farmacológico , Glucocorticoides/uso terapêutico , Memantina/uso terapêutico , Metilprednisolona/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Doença de Parkinson Secundária/tratamento farmacológico , Intoxicação por Monóxido de Carbono/complicações , Intoxicação por Monóxido de Carbono/diagnóstico , Transtornos Cerebrovasculares/induzido quimicamente , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/fisiopatologia , Quimioterapia Combinada , Humanos , Oxigenoterapia Hiperbárica , Masculino , Pessoa de Meia-Idade , Síndromes Neurotóxicas/diagnóstico , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/fisiopatologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/diagnóstico , Doença de Parkinson Secundária/fisiopatologia , Imagem de Perfusão/métodos , Pulsoterapia , Recuperação de Função Fisiológica , Fatores de Tempo , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
19.
J Stroke Cerebrovasc Dis ; 23(3): 566-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23660345

RESUMO

We describe asymptomatic sinus arrest and post-hiccup cough syncope in a patient with medullary infarction. A 78-year-old woman developed arrhythmia, hiccup, and cough syncope attacks. Neurological examination was not remarkable. Cough syncope occurs after hiccup attacks. Bradycardia and decreased blood pressure were also present after the beginning cough. Holter 24-hour electrocardiography monitor exhibited 65 episodes of asymptomatic sinus arrest more than 3 seconds. Magnetic resonance imaging disclosed acute infarction in the bilateral medial regions and the right tegmentum of the upper and middle medulla oblongata. Cerebral angiography showed severe atherosclerotic changes in the vertebral arteries. These clinicoradiological findings suggested that a distinct topography of medullary lesions could cause a series of cardiovascular and respiratory dysfunction. Thus, physicians should pay more attention to the medullary lesion in patients with arrhythmia and syncope.


Assuntos
Infartos do Tronco Encefálico/complicações , Tosse/etiologia , Soluço/etiologia , Parada Sinusal Cardíaca/etiologia , Síncope/etiologia , Idoso , Doenças Assintomáticas , Pressão Sanguínea , Bradicardia/etiologia , Infartos do Tronco Encefálico/diagnóstico , Angiografia Cerebral , Tosse/diagnóstico , Tosse/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca , Soluço/diagnóstico , Soluço/fisiopatologia , Humanos , Hipotensão/etiologia , Parada Sinusal Cardíaca/diagnóstico , Parada Sinusal Cardíaca/fisiopatologia , Síncope/diagnóstico , Síncope/fisiopatologia
20.
J Stroke Cerebrovasc Dis ; 23(1): 187-90, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23265779

RESUMO

A 64-year-old obese man developed hypesthesia in the left arm and leg. Neurological examination revealed decreased senses of pain, touch, and temperature in the left face, arm, trunk, and leg. Remaining functions were normal. Electrocardiogram showed atrial fibrillation. Somatosensory-evoked potentials using the stimulation in the median nerve were normal on both sides. Brain magnetic resonance imaging revealed acute infarction in the right parietal operculum and insula. There were no pathognomonic lesions in the postcentral gyrus, the thalamus, or the brain stem. Cardioembolic operculo-insular infarction was diagnosed. Diffusion tensor tractography map displayed the thalamocortical projections to the primary and the secondary somatosensory cortex (S2). These radiological findings supported that the operculo-insular lesion could disrupt the thalamo-S2 pathway. Thus, the thalamocortical disconnection between the thalamus to the S2 could cause superficial hemisensory dysfunction in the present patient.


Assuntos
Córtex Cerebral/patologia , Infarto Cerebral/complicações , Infarto Cerebral/patologia , Transtornos de Sensação/etiologia , Transtornos de Sensação/patologia , Córtex Somatossensorial/patologia , Tálamo/patologia , Infarto Cerebral/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/patologia , Exame Neurológico , Obesidade/complicações , Radiografia
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